Complex oxide

A complex oxide is a chemical compound that contains oxygen and at least two other elements (or oxygen and just one other element that's in at least two oxidation states). Complex oxide materials are notable for their wide range of magnetic and electronic properties, such as ferromagnetism, ferroelectricity, and high-temperature superconductivity. These properties often come from their strongly correlated electrons in d or f orbitals.

Many minerals found in the ground are complex oxides. Commonly studied mineral crystal families include spinels and perovskites.

Complex oxide materials are used in a variety of commercial applications.

Magnets made of the complex oxide ferrite are commonly used in transformer cores and in inductors. Ferrites are ideal for these applications because they are magnetic, electrically insulating, and inexpensive.

Piezoelectric transducers and actuators are often made of the complex oxide PZT (lead zirconate titanate). These transducers are used in applications such ultrasound imaging and some microphones. PZT is also sometimes used for piezo ignition in lighters and gas grills.

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